Two glass capillary tubes of inside diameters of 20 and 13 microns are used to test the capillary rise in an annular cross section .The wall thickness of each capillary is 2 microns .The smaller capillary tube is inserted in the larger one so that an annular space is created .
a) Derive an equation which describes the capillary rise in an annular space.
b) Calculate the rise of water in the inner capillry and in the annular space . The surface tension between the air and water 71.97 dynes/cm and the contact angle between air and water on a glass surface is 0 degrees.
c) Calculate the capillary pressure for the inner capillary tube and the annular space in units of atm